A further eight members of staff have been suspended from Muckamore Abbey Hospital.
They have been placed on precautionary suspension from the hospital while police investigations into abuse allegations continue.
The move followed viewing of CCTV footage at the facility, the Belfast Health and Social Trust have said.
The County Antrim hospital caters for vulnerable adults with severe learning disabilities and mental health needs.
It brings the total number of staff currently suspended from the hospital to 28.
Last month, the police officer leading the investigation into the facility said CCTV footage had revealed 1,500 crimes on one ward of the hospital.
Allegations of ill treatment began to surface at Muckamore in November 2017 when it was revealed four staff members had been suspended.
In August 2018, BBC News NI reported there had been 53 assaults on patients by staff reported at the hospital – five of those incidents were investigated and substantiated.
It emerged earlier in September that the Department of Health had ordered a new review into the hospital.